dfan

If this article gets even one author to stop using < and > when they mean \langle and \rangle, it will be worth it.

This is not purely an AI phenomenon, although AIs are less likely to feel guilty about it. A game from the European Go Championship in 2002 was decided by just this sort of rules-lawyering ("obviously" dead stones were not technically correctly marked as dead, so one of the players claimed they were alive). The result was later overturned to match what a human player would expect.

https://senseis.xmp.net/?DisputeMeroJasiek https://senseis.xmp.net/?DisputeMeroJasiek%2FDiscussion

I disagree with the second paragraph but not enough to get into a public debate about it. But it is worth pointing out that Carlsen's 53-game streak was a non-loss streak, not a win streak. Many of those games were draws.

The Elo system is calibrated so that that the expected value from playing a player 200 points stronger than you is 0.24. This is true independent of the strength of the players. If you are scoring 0.10 against players 200 points stronger than you (that would mean, for example, 1 draw and 4 losses over 5 games) but maintaining a stable rating, then you must be crushing players that are weaker than you and/or doing very well against players at your level.

(FWIW, I am 2000 USCF and an expected value of 0.24 vs a 2200 and 0.76 vs an 1800 feels quite reasonable to me.)

You may be interested in Quantum Chess (https://quantumchess.net/how-to-play/).

Inform 7 is the closest thing I can think of to "everything is a graph". Basically, objects in the world are vertices and relations are edges. When you first encounter relations they don't necessarily seem that exciting, but it turns out that having relationships between objects be a first-class concept really changes the way you think about and design systems.

Think of it this way. The article presents a random-gap list with only five entries, and it looks terrible; the most common page occurs 9 times as often as the least common.

Now think about a random-gap list with five million entries. With that many entries, will the gaps balance out? In the best case, five of them end up in the range from 0 to 1 millionth, five of them end up in the range from 1 millionth to 2 millionths, etc. But we've already seen what it looks like to have five uniform random numbers in a range (whether it's big or small doesn't matter); the gaps tend to be really varied. So we're going to get this sort of imbalance between gap sizes (viewed as a ratio) no matter how many entries we insert.

One other thought experiment: the article mentioned a page with a gap size of one billionth. How many pages will it take for that to balance out so that page doesn't have an unusually small gap any more? How many pages does Wikipedia have?

(This is similar to the reason that infinite space packed with marbles has the same packing density as infinite space packed with bowling balls.)

There was a fun Hacker News post last year that consisted just of searching HN comments for the phrase "why not simply": https://news.ycombinator.com/item?id=27415725

I was very surprised to see a headline involving "Harvard mathematician" and "chess problem" and find that the article was not about Noam Elkies.

You might enjoy the extra challenge of hard mode (access it through the gear icon), where every guess you make has to be a potential solution based on the existing history.

Well over a decade ago, I spent an afternoon in a stationery store trying out as many pens as I could. I fell in love with the Pentel EnerGel NV 0.5mm (smooth, dark, consistent, feels nice in the hand) and haven't looked back since. I'm glad to see that this website has a high opinion of it too.

Kenneth Regan's work on Intrinsic Performance Ratings includes estimated ratings for Morphy, which vary widely from event to event but average around 2300, which I think matches the intuitive perception of his strength that modern strong players have. https://cse.buffalo.edu/~regan/papers/pdf/Reg12IPRs.pdf

(Of course, as with all historical players, he would be stronger if he were re-animated today and exposed to modern principles and openings.)

I associate some pitch classes with colors and I think it's because of a toy glockenspiel I had when I was a kid.

I'd start considering players to be "pro" at around 2600 lichess rapid, which is a pretty normal rating for an International Master. (Mine is over 2200 and I just consider myself to be pretty good.)

1800 is still in the "learning how to play well" stage but getting there from a standing start in 6 months is indeed nice progress. He doesn't seem to claim it's anything more than that, which I appreciate.

Previous discussion: https://news.ycombinator.com/item?id=19692418

You could probably perform some sort of math personality test by asking which proof the respondent likes best! I was particularly charmed by #5 (construct a volume of revolution, then slice it two ways).

I don't remember hearing about other developers doing the same thing. I think it was just that I had a lot of experience debugging deterministic programs (like command-line tools) and it was infinitely more pleasant than trying to debug an interactive graphical program, so it was worth seeing whether we could make the game itself deterministic.

I've never made a system that ambitious again, but one thing I've learned from that experience is to never ever call global rand(); always always create your own RNGs that you can run explicitly, and if you have multiple systems that can be disabled independently (e.g., we were able to turn off graphics during our replays), give them each their own RNG.

For the DOS game Terra Nova (1996) I made our game engine fully deterministic. I guess this was a year before Age of Empires but well after you. It was amazing how much easier this made debugging. The effect was so great that I can't even put a multiplier on it, because it moved bugs from the "we'll never reproduce this" category to the "just see what happened and fix it" category. Some of these replays represented more than half an hour of gameplay too.

One thing that surprised me is that it also found a bunch of bugs waiting to happen (uninitalized variables / dangling pointer sort of stuff) that would trigger an error when replaying from a file didn't produce the same results as the original play (we had a checksum of game state that we could check).

"Does it take into account the additional co2 that fishing boats emit?"

Yes.

"Unlike previous studies that have largely overlooked the downstream processing activities associated with Alaskan pollock, this study examined all the components of the supply chain, from fishing through the retail display case." [https://news.ucsc.edu/2020/01/mckuin-fish.html]

I used Sibelius for years and am happy to have switched to Dorico.

Dorico is indeed better, and definitely not a copy of Sibelius UI-wise. Not only was the team starting over with a lot more experience under their belt, but they also had a much better idea of what didn't scale (from a user interface perspective) from the original Sibelius to its current incarnation, which has tons more features.

It's worth pointing out that when Sibelius was first released, it was hugely nicer to use than the industry-leading product at the time (Finale).

This is my favorite "easily explainable to someone who doesn't know math but still very interesting" problem.

Underworld developer here. We certainly started it before we got the deal with Origin, but a lot of the design was done afterwards with the fact that it was an Ultima in mind. I'll grant that its Ultima-ness was thinner compared to many of the games with Roman numerals on them.

Ultima Underworld II, of course, was designed to be an Ultima game from the start.

In chess, at least, all calculations in a single tournament are indeed batched.

It's worth noting that this approach, of training a neural net on human games of a certain level and not doing tree search, has been around for a few years in the Go program Crazy Stone (https://www.remi-coulom.fr/CrazyStone/). (There wasn't a paper written about it so it's not common knowledge, and I assume the authors of this paper weren't aware of it or they would have cited it.)

Good call! I love Tichu. I'd put it just a touch behind the other games I listed.

I've spent thousands of hours of my life playing and studying chess and go. There are very few games that are rich enough to come close to holding my interest as much as those; poker, Titan, and Diplomacy are the only ones that immediately come to mind. Then last year I finally delved into 18xx (I had vaguely known about the genre for decades) and it leaped into that list as well.

There have been a few projects to make these games playable on computers over the years, but http://18xx.games/, launched this year, is in my opinion clearly the best (disclaimer: I'm a contributor to the codebase). Ideally you can find a game with experienced players who are eager to help a newbie learn the ropes.

The terminology associated with chess challenges [to use a neutral term] is unfortunate.

"Chess problem" is a term of art that refers to an artificial composed position with a unique solution that is constructed to both be a challenge to the solver and have aesthetic value. They often have constraints on the solution such as that White must deliver checkmate in two moves (three ply). This is what I assume you're referring to.

A position from an actual game (or that easily could have been) that demonstrates a tactic (or combination of them) is generally known as a "chess puzzle", largely because the term "chess problem" was already squatted on.

Somewhere in between the two is the "study", which is a constructed position, less artificial than a chess problem but still very carefully made to have a unique solution that walks a tightrope and generally requires absolutely exact calculation rather than working by general tactical principles.

It was very common in the past for composers to learn the craft by copying out the musical scores of the masters.

This is also why I always type in all the examples from programming books instead of cutting and pasting.

She goes into detail about this in the article that is linked to later in the paragraph you quote.